While our economy is humming with 3.1% GDP growth in 17Q2 and 3% growth in 17Q3, these rates are unsustainable. That’s because these rates have required such large increases in employment that the unemployment rate declined from a low 4.5% at the end of March to a staggeringly low 4.2% by the end of September. We will soon run out of workers! Only by boosting labor productivity can this continue.